黄鳍鲷基因组微卫星的分离

采用磁珠富集法构建黄鳍鲷(Acanthopagrus latus Houttuyn)基因组微卫星富集文库。共挑选60个克隆进行测序,分析发现58个克隆分别含(GA)n或(CA)n两碱基重复单元。进一步通过序列比对,最终获得41个具有特异微卫星序列的阳性克隆。其中,23个克隆含有(GA)n或(CT)n两碱基重复序列,17个克隆含有(GT)n或(CA)n重复序列,另1个含有以上两种重复类型。获得的微卫星序列中,单一型及间断型序列各有20条,另有1条属于复合型序列。序列长度为117~512 bp,平均259 bp。微卫星核心序列两碱基重复5到38次,绝大多数序列重复次数大于10。基于微卫星两端的侧翼序列设计并获得了3对能够在黄鳍鲷基因组有效扩增的微卫星引物。本研究旨为进一步开展黄鳍鲷分子育种及资源评价分析提供基础资料。

Isolation of microsatellites from yellowfin seabream Acanthopagrus latus

Microsatellite-Enhanced Genomic Library of the yellowfin seabream Acanthopagrus latus was constructed using repeat-enrichment method with biotin-labeled oligos and streptavidin magnetic beads.Sixty positive clones were selected and sequenced,of which 58 clones are discovered to contain microsatellites with two nucleotide repeats of(GA)n or(CA)n.By alignment,41 special microsatellite clones are confirmed finally among which 23 clones contain(GA)n or(CT)n,17 contain(GT)n or(CA)n,and one contains(GA)n and(CA)n.In addition,the microsatellites can be divided into three types of 20 pure sequences,20 interrupted sequences and one compound sequence.The sequence sizes range from 117 bp to 512 bp with an average of 259 bp.The repeats of two nucleotides within core sequences are 5 to 38 times,and most of them are more than 10 times.Three microsatellite primer pairs are designed based on the tandem sequences of microsatellites,and further were confirmed to be effective in the amplification of the genome DNA of the yellowfin seabream.This study provides a base for molecular breeding and assessment of germplasm resources of the yellowfin seabream.